I believe the fruit bushes
should be fine. I don't have much
experience at all for your zone--I live and garden in zone 8! But I would think about planting some insectory plants or herbs--most things with flowers will attract insects, and it's even better if you have something that will flower three seasons, from spring bulbs to autumn asters.
Some nutrient accumulators would help improve your soil--comfrey is a
permaculture favorite here, but most anything with a deep taproot will be good--I let my dandelion,
nettle, and dock spring up, and then chop and drop them periodically; and maybe some nitrogen-fixing plants or cover crops such as clover--which also doubles as an insectory plant. I think caragana is nitrogen-fixing, so depending on how close it is to your other plantings, you may not need many (or any) other N-fixers. The hedge clippings could double as mulch too, for soil improvement: something I do with pretty much all my prunings unless I'm pruning with a handsaw.
Have you read
Gaia's Garden by Toby Hemenway? I have found this book very helpful for putting together my own (new) food forest. His
books explains the roles of the plants (and other living things) much more elegantly than I can!